Increasing the publics knowledge and interest in improving the energy rating of their property is key to transforming the nations housing stock, the Federation of Master Builders (FMB) has said.Speaking during the recent Cut the Carbon online seminar, Brian Berry, director of external affairs at the FMB, noted that the construction industry currently faces a number of challenges in attempting to meet the governments sustainable home targets.There is an absence of a strong consumer demand at present, there is an absence of a clear delivery plan set out by government and there is an absence of knowledge and skills, he said.Mr Berry added that the government should consider introducing a sustainability code for existing homes as well as giving builders more training.The comments come after James Max, an LBC (Londons Biggest Conversation) radio presenter, recently suggested that conditions are currently right for homeowners with a healthy disposable income to invest in their properties. This could include installing a new kitchen sink or set of taps.